Oil and gas companies use drilling rigs to extract crude oil or natural gas from the earth. We discuss accidents that took place on the drilling rig which are known as drilling rig accidents. also Reasons for Drilling Rig Accidents? and worst oil drilling rig accidents in history.
What is Drilling Rig?
Oil and gas companies use drilling rigs to extract crude oil or natural gas from the earth. The term “rig” refers to the sophisticated engineering required for the task. Drilling rigs are complex systems that rely on both man and machine to bore into soil and rock in order to extract fuel from the earth and then process it into marketable petroleum products.
Reasons for Drilling Rig Accidents?
The most common forms of offshore oil and gas drilling disasters in recorded human history have been rig explosions, fires in the drilling rig, capsizing/sinking, oil spills, and the loss of workers who worked in the drilling rig and marine lives.
As investigations show, in some of the world’s worst offshore oil rig disasters, a large number of these drilling rig accidents could have been avoided. Among the leading causes of drilling rig accidents are listed below in this article here
Blowouts in Drilling Rigs
Offshore drilling rig explosions and oil spills are most commonly caused by blowouts. Rig blowouts occur when an uncontrolled release of oil or gas from the well occurs as a result of pressure control system failure.
The worst blowout disaster in recent history was the BP Deepwater Horizon explosion in April 2010, which killed 11 rig workers and spilled more than four million barrels of oil into the Gulf of Mexico.
Other major blowout disasters throughout history include:
- The Santa Barbara oil spill off the coast of California in January 1969
- In June 1979, the Ixtoc I oil spill occurred in the Gulf of Mexico’s Bay of Campeche.
- In August 1984, the Enchova Central Platform disaster occurred in Brazil’s Campos Basin.
- On 30 June 1964, the C.P. Baker Drilling Barge sank in the Gulf of Mexico, and
- in August 2009, the Seadrill’s West Atlas rig sank in the Timor Sea off the coast of Australia.
These are the biggest drilling rig accident caused by Blowouts.
Strong winds and rouge waves
Typhoons, hurricanes, storms, and rouge waves can also cause explosions, as well as flooding, capsizing, and sinking of offshore drilling rigs.
The Alexander L Kielland drilling rig accident in 1980 in the Norwegian Continental Shelf killed 123 people, the Seacrest Drillship disaster in 1989 in the Gulf of Thailand killed 91 people, the Ocean Ranger oil rig disaster in 1982 in the North Atlantic Sea, Canada killed 84 people, and the Glomar Java Sea Drillship disaster in 1983 workers in the South Pacific died.
Another major drilling rig disaster caused by natural forces was the 1979 Bohai 2 oil rig disaster off the coast of China, which killed 72 people. After strong winds broke the ventilator pump and caused a puncture hole in the deck, resulting in extensive flooding, the jack-up rig capsized and sank. Extreme waves striking the platform tower caused the Abkatun Permanente oil platform explosion in the Gulf of Mexico in 2015, killing four people.
Collisions in drilling rig
Oil and gas leaks, as well as water flooding, are among the most common causes of drilling rig disasters. The Mumbai High North disaster, which occurred off the western coast of India in the Arabian Sea in 2005, was caused by a collision with a multipurpose support vessel (MSV), which caused the platform’s gas export risers to rupture, resulting in a gas leak and explosion.
The 2007 Usumacinta Jack-up disaster in the Gulf of Mexico’s Bay of Campeche was also caused by a collision with the PEMEX-operated Kab-101 platform. The platform’s cantilever deck collides with a production valve tree as a result of the oil and gas leak.
Equipment failures and structural issues
While natural disasters are still a possibility, faulty equipment and structural flaws are the leading causes of drilling rig accidents. Equipment failure and a lack of seaworthiness on the drilling platforms have been blamed for some of the most serious offshore drilling rig disasters.
One of the bracings attached to one of the platform legs, for example, failed to withstand strong winds and high waves, resulting in the capsizing of the Alexander L Kielland platform (March 1980), Norway’s worst offshore disaster, which killed 123 people. An undetected fatigue crack in the weld of an instrument connection on the bracing was identified as the root cause of this disaster.
The Deepwater Horizon disaster, which was caused by the failure of the blowout preventer, is another example of how a single piece of equipment malfunctioning can lead to a full-blown disaster. Similarly, the 2001 explosions on the Petrobras P-36 semi-submersible oil platform off the coast of Brazil were thought to be caused by a ruptured emergency drain tank caused by increased pressure.
Inadequate safety procedures in Drilling Rig
Despite being surrounded by water, offshore drilling rigs face a high risk of fire and explosion due to the nature of the operation. A small spark or uncontrolled gas leakage can have disastrous consequences due to the high concentration of flammable materials on and near the rig. As a result, offshore drilling necessitates extreme caution and strict adherence to safety protocols.
The Piper Alpha disaster in the UK North Sea in 1988, which killed 167 people, was caused by a communication error, which resulted in a tragic safety lapse. Because the maintenance work had not been completed, the pressure valve of one of the condensate-injection pumps was removed as part of routine maintenance, and the condensate pipe was temporarily sealed with two blind flanges during a shift change in the evening.
In 1988, the most dangerous offshore oil rig accident occurred in the North Sea of the United Kingdom. The accident was dubbed the Piper Alpha disaster. The accident killed 167 people. It was caused by a breakdown in communication, which also resulted in a safety error. Because the maintenance work had not been completed, the pressure valve of one of the condensate-injection pumps was removed as part of routine maintenance, and the condensate pipe was temporarily sealed with two blind flanges during the evening shift change.
The maintenance crew, unaware that the maintenance crew had removed the safety valve, activated an alternate pump. The temporary seal couldn’t withstand the pressure, resulting in gas leakage, ignition, and explosions. Another example of unsafe behavior resulting in offshore rig disasters is the 2012 explosion of the Black Elk Energy production platform, which killed three contract workers and oil spilled into the Gulf of Mexico. When a worker attempted to weld a pipe near an oil line, the acetylene flame ignited a fire.
The very worst oil drilling rig accidents in history
Piper Alpha in the UK North Sea in 1988
Following the discovery of crude reserves in 1973, the US-based Occidental managed Piper Alpha, which is located 120 miles northeast of Aberdeen, Scotland. It is one of the largest offshore oil platforms in the United Kingdom. In 1988, 167 people were killed in explosions on the Piper Alpha oil platform in the British North Sea. This is one of the deadliest oil rig accidents in history.
Alexander L Kielland in the Norwegian North Sea in 1980
The semi-submersible platform Alexander L Kielland housed 212 workers on the evening of March 27, 1980. When the floating hotel capsized, 123 workers ranging in age from 19 to 57 died. A bridge linked the ‘flotel’ to the Edda 2/7C drilling platform, which was extracting on the North Sea’s Ekofisk field. Ekofisk is located about 235 miles east of Dundee, Scotland on the Norwegian continental shelf.
Seacrest Drillship disaster in the South China Sea in 1989
The Seacrest Drillship Accident in the South China Sea killed 91 workers. Typhoon Gay produced 40-foot-high waves that night, causing the drillship to capsize.
Ocean Ranger oil rig disaster in the Canadian Atlantic Ocean in 1982
The Ocean Ranger disaster claimed the lives of 84 crew members on February 15, 1982. They were on board the rig when it capsized and sank in the North Atlantic Sea off the coast of Newfoundland, Canada. The 396ft long, 262ft wide, and 337ft tall 25,000t rig was the largest of its kind at the time. From 1,500 feet underwater, the semi-submersible mobile oil drilling could drill up to 25,000 feet below the seabed.
Glomar Java Sea drillship disaster, South China Sea, 1983
On October 25, 1983, six years before the Seacrest disaster, the Glomar Java Sea Drillship capsized in the South China Sea. The drillship capsized and sank approximately 63 nautical miles south-west of Hainan Island, China, and 80 nautical miles east of Vietnam, killing 81 people.